60489-11-4Relevant academic research and scientific papers
Structural and electrochemical characterization of metallo-porphyrins intercalated into ZnCr-layered double hydroxides: Some evidence of dimer formation
Taviot-Gueho, Christine,Halma, Matilte,Charradi, Khaled,Forano, Claude,Mousty, Christine
, p. 1898 - 1905 (2011)
In this study, inorganic-organic hybrids were prepared by intercalation of metal complexes (Zn and Fe) of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TSPP) into Zn2Cr layered double hydroxides (LDH) by coprecipitation method at constant pH. The resulting materials were characterized by powder X-ray diffraction, UV-Vis and FTIR spectroscopies showing the intercalation of porphyrins between the ZnCr layers. While monomer species are intercalated in the case of Zn2Cr-ZnTSPP, the intercalation of dimers is likely to occur in the case of Zn2Cr-FeTSPP. In both materials, a perpendicular orientation of the porphyrin ring against the hydroxide layers is proposed. Of particular interest is the good stability of ZnCr-LDH host over a wide pH range. The electrochemical behavior of these hybrid materials in both neutral (pH 7.0) and acid media (pH 4.5) was investigated by cyclic voltammetry. Zn 2Cr-FeTSPP exhibits an electrocatalytic activity for the reduction of oxygen, hydrogen peroxide and nitrite.
Efficient H2O2 oxidation of organic pollutants catalyzed by supported iron sulfophenylporphyrin under visible light irradiation
Huang, Yingping,Li, Jing,Ma, Wanhong,Cheng, Mingming,Zhao, Jincai,Yu, Jimmy C.
, p. 7263 - 7270 (2004)
An efficient method has been developed to degrade toxic and nonbiodegradable organic pollutants such as Sulforhodamine B (SRB) and 2,4-dichlorophenol (DCP). It is based on the photocatalytic power of iron tetrasulfophenylporphyrin supported on a commercial anionic ion-exchange resin (Amberlite IRA 900) (FePR) to activate an oxidant H2O2 in aqueous media. Visible light irradiation (?? > 450 nm) significantly accelerates the degradation process. The new catalyst is effective over a wide pH range, and can be easily recycled by filtration. The SRB and DCP were mineralized with yields of 56% and 68% at a catalyst/substrate molar ratio of 1:33 and 1:535, respectively. Moreover, the supported-catalyst would suppress greatly the undesirable side-reaction of H2O2: conversion to O2. UV-vis spectroscopy, high-performance liquid chromatography, ion chromatography, IR, spin-trapping electron paramagnetic resonance, surface photovoltage spectroscopy, and total organic carbon measurements were used to examine the photoreaction processes. The photocatalytic degradation pathways mainly involve the formation and reaction of ?·OH radicals. On the basis of the experimental results, a possible reaction mechanism is proposed.
Water-Soluble Nitroxyl Porphyrin Complexes FeIITPPSHNO and FeIITPPSNO- Obtained from Isolated FeIITPPSNO·
Mazzeo, Agostina,Pellegrino, Juan,Doctorovich, Fabio
, p. 18521 - 18530 (2019/11/21)
The first biomimetic water-soluble FeII-porphyrin nitroxyl complexes were obtained and characterized by UV-vis in protonated and deprotonated forms by reduction of previously isolated and characterized FeIITPPSNO·. The pKa involved in the FeII-HNO → FeII-NO- + H+ equilibrium was estimated to be around 9.7. The FeIITPPSHNO complex spontaneously reoxidizes to the nitrosyl form following a first-order kinetic decay with a measured kinetic constant of k = 0.017 s-1. Experiments show that the HNO adduct undergoes unimolecular homolytic cleavage of the H-NO bond. DFT calculations suggest a phlorin radical intermediate for this reaction. The deprotonated NO- complex resulted to be more stable, with a half-life of about 10 min.
